1. Technical Field
The present disclosure relates to a magnetic device. More particularly, the present disclosure relates to a magnetic device in a voltage module.
2. Description of Related Art
In order to meet the needs of low voltage and large current required in modern electronic products, voltage regulator modules (VRM) (also referred to as voltage converters) usually have to convert a high voltage into different low voltages for powering various devices (e.g., a central processing unit). Conventionally, a magnetic device (e.g., an inductor) is an essential component in a VRM, and its volume, conduction loss, inductance, etc., are major factors which affect operating characteristics of the VRM, such as current ripple, efficiency, dynamic operating speed, etc. In practice, integrated magnetics can be utilized for fabrication of the magnetic device, such that the volume of the magnetic device can be reduced and performance of the VRM can be improved.
However, a conventional magnetic device typically has several leakage inductance paths therein during operation, such that the leakage inductances of the whole coupled inductance is too large, further resulting in an increase in conduction losses of windings.
Moreover, the leakage inductances generated by the conventional magnetic device cannot be effectively concentrated, so that the leakage inductances are distributed non-uniformly, thus causing ripples of output voltages of a VRM to be increased significantly.
In addition to the technique of adopting integrated magnetics to generate mutual inductance coupling, auxiliary windings can also be used to generate inductance coupling. However, even though the technique of utilizing auxiliary windings can help balance the current generated by each inductor and reduce current ripples, utilizing such a technique may cause an additional problem of conduction losses of windings.